Main Polar Metabolites from Leaves of the Native Andean Species Jungia rugosa Less (Asteraceae)

The ethanolic extract of Jungia rugosa Less, a popular Andean species belonging to the family Asteraceae, was characterized chemically. The extract was deprived of chlorophyll by solid-phase extraction, using Diaion Hp-20 resin as solid phase, and eluting with a mixture of EtOH/H2O according to a decreasing polarity gradient. The chlorophyll-free extract was then repeatedly fractionated by open column chromatography in normal phase and preparative thin layer chromatography. Two main metabolites were finally purified and identified through structure elucidation. Nuclear magnetic resonance spectroscopy (NMR) and electrospray ionization-mass spectrometry (ESI-MS) were the 2 techniques used for analysis. The identified metabolites were coumarins: (1) umbelliferone and (2) coumarin-5- methyl-4α-glucoside. Compound 1 is known in the literature for having anti-inflammatory, antihyperglycemic, and antitumor activities. Compound 2 has not been described before for this botanical genus and its pharmacological effects are still uninvestigated. Keywords: Jungia rugosa, umbelliferone, coumarin-5-methyl-4-glucoside, NMR, ESI-MS, Ecuador. Resumen Se caracterizó químicamente el extracto etanólico de Jungia rugosa Less, una popular especie andina perteneciente a la familia Asteraceae. Se eliminó las clorofilas al extracto mediante extracción en fase sólida, utilizando como fase sólida resina de Diaion Hp-20 y eluyendo con una mezcla de EtOH/H2O según un gradiente de polaridad decreciente. El extracto libre de clorofila se fraccionó repetidamente mediante cromatografía en columna abierta en fase normal y cromatografía en capa fina preparativa. Finalmente, se purificaron e identificaron dos metabolitos principales mediante la elucidación de la estructura. Se utilizaron espectroscopía de resonancia magnética nuclear (RMN) y espectrometría de masas de ionización por aspersión de electrones (ESI-MS). Los metabolitos identificados fueron las cumarinas: umbeliferona (1) y cumarina-5-metil-4α-glucósido (2). El compuesto 1 es conocido en la literatura por tener actividad antiinflamatoria, antihiperglucémica y antitumoral. El compuesto 2 no se ha descrito antes para este género botánico y sus efectos farmacológicos aún no se han investigado. Palabras Clave: Jungia rugosa, umbeliferona, cumarina-5-metil-4-glucósido, RMN, ESI-MS, Ecuador

Semi-synthetic Derivatives of Limonin A: Synthesis Using Basic Hydrolysis and Reduction with NaBH4

Limonin A (L-A) was obtained from seeds of Citrus sinensis that were dried, grounded, and extracted using Soxhlet equipment. Initially, 100% hexane was used to eliminate fats, and finally, 100% dichloromethane was used in order to concentrate and isolate the compound. L-A recrystallization was performed using acetic acid. The purified fraction was identified as limonin according to spectral nuclear magnetic resonance (NMR) data. Two reactions were performed from L-A: Basic hydrolysis that acted on the A’ lactone ring producing a sodium salt of the lactone, and reduction with NaBH4 to reduce the carbonyl of carbon C-7 and generate the corresponding alcohol limonol. The structural modification of abundant secondary metabolites can become a source of new products with biological activity, useful in the pharmaceutical, cosmetic, and agrochemical industries of natural origin. Keywords: limonin, semisynthetic derivates, bioactive compounds, non-timber forest products. Resumen La limonina A (L-A) se obtuvo a partir de semillas de Citrus sinensis, que fueron secadas, molidas y extraídas en equipo Soxhlet, utilizando inicialmente hexano al 100% para eliminar grasas y finalmente diclorometano al 100% para concentrar y aislar el compuesto. La re cristalización de la L-A se realizó utilizando ácido acético. La fracción purificada se identificó como limonina, acorde a los datos espectrales de RMN (Resonancia Magnética Nuclear). A partir de la Limonina A se realizaron dos reacciones: Hidrólisis básica que actuó sobre el anillo de lactona A’ produciendo la sal sódica de lactona y reducción con NaBH4 para reducir el carbonilo del carbono C-7 y generar el correspondiente alcohol limonol. La modificación estructural de metabolitos secundarios abundantes puede convertirse en una fuente para generar nuevos productos con actividad biológica, útiles en las industrias farmacéutica, cosmética y agroquímica de origen natural. Palabras Clave: Limonina; derivados semisintéticos, compuestos bioactivos, productos forestales no maderables

Localization of gravity on a de Sitter thick braneworld without scalar fields

In this work we present a simple thick braneworld model that is generated by an intriguing interplay between a 5D cosmological constant with a de Sitter metric induced in the 3-brane without the inclusion of scalar fields. We show that 4D gravity is localized on this brane, provide analytic expressions for the massive Kaluza-Klein (KK) fluctuation modes and also show that the spectrum of metric excitations displays a mass gap. We finally present the corrections to Newton's law due to these massive modes. This model has no naked singularities along the fifth dimension despite the existence of a mass gap in the graviton spectrum as it happens in thick branes with 4D Poincare symmetry, providing a simple model with very good features: the curvature is completely smooth along the fifth dimension, it localizes 4D gravity and the spectrum of gravity fluctuations presents a mass gap, a fact that rules out the existence of phenomenologically dangerous ultralight KK excitations in the model. We finally present our solution as a limit of scalar thick branes.Comment: 11 pages in latex, no figures, title and abstract changed, a new section and some references adde

Efectividad y seguridad comparada de inhibidores del cotransportador sodio-glucosa tipo 2 (iSGLT2) en diabetes mellitus tipo 2: revisión rápida de revisiones sistemáticas y metaanálisis

Objetivo: recopilar y evaluar la evidencia disponible respecto a la efectividad y seguridad comparada de inhibidores del cotransportador de sodio glucosa tipo 2 (iSGLT2) en pacientes con diabetes mellitus tipo 2. Metodología: se realizó una revisión sistemática rápida de revisiones sistemáticas de iSGLT2 en las bases de datos Medline y Embase hasta septiembre de 2019. El desenlace primario cardiovascular incluyó eventos adversos cardiovasculares mayores (MACE) que corresponden a muerte por causa cardiovascular, ataque cerebrovascular (ACV) no fatal, infarto agudo de miocardio (IAM) no fatal, además de hospitalización por insuficiencia cardíaca; desenlace renal (definido como progresión de enfermedad renal), disminución de la tasa de filtración glomerular (TFG) y de la relación albuminuria-creatinuria. El desenlace de seguridad agrupó hipoglucemia, fracturas, infecciones urinarias, entre otros. La calidad metodológica de las revisiones se evaluó con el instrumento A measurement Tool to Assess Systematic Review (AMSTAR-2) modificado. Resultados: se incluyeron 5 revisiones sistemáticas de la literatura de calidad media y alta según AMSTAR-2 modificado, entre las cuales se encontró que los iSGLT2 reducen el riesgo de mortalidad cardiovascular en un 23 %, de mortalidad por todas las causas en 20 % y en admisión hospitalaria por insuficiencia cardíaca en un 33 %, en comparación con el cuidado estándar. En cuanto al desenlace renal, los iSGLT2 enlentecen el deterioro de la enfermedad renal y reducen la progresión a albuminuria en pacientes con proteinuria ya documentada. En el desenlace de seguridad se observa una mayor posibilidad de desarrollar infecciones del tracto genitourinario respecto a antidiabéticos orales. Conclusiones: la evidencia sugiere que los iSGLT2 son efectivos en la reducción del riesgo de mortalidad cardiovascular, de mortalidad por todas las causas, de admisión hospitalaria por insuficiencia cardíaca, de progresión de la nefropatía y del desarrollo de enfermedad renal en estadio final. En desenlaces de seguridad, la evidencia sugiere que los iSGLT2 tienen menor riesgo de eventos de hipoglucemia

Building an Efficient Cluster Cosmology Software Package for Modeling Cluster Counts and Lensing

We introduce a software suite developed for galaxy cluster cosmological analysis with the Dark Energy Survey Data. Cosmological analyses based on galaxy cluster number counts and weak-lensing measurements need efficient software infrastructure to explore an increasingly large parameter space, and account for various cosmological and astrophysical effects. Our software package is designed to model the cluster observables in a wide-field optical survey, including galaxy cluster counts, their averaged weak-lensing masses, or the cluster's averaged weak-lensing radial signals. To ensure maximum efficiency, this software package is developed in C++ in the CosmoSIS software framework, making use of the CUBA integration library. We also implement a testing and validation scheme to ensure the quality of the package. We demonstrate the effectiveness of this development by applying the software to the Dark Energy Survey Year 1 galaxy cluster cosmological data sets, and acquired cosmological constraints that are consistent with the fiducial Dark Energy Survey analysis

The MADPSZ catalogue of Planck clusters over the DES region: extending to lower mass and higher redshift

We present the first systematic follow-up of Planck Sunyaev-Zeldovich effect (SZE) selected candidates down to signal-to-noise (S/N) of 3 over the 5000 deg$^2$ covered by the Dark Energy Survey. Using the MCMF cluster confirmation algorithm, we identify optical counterparts, determine photometric redshifts and richnesses and assign a parameter, $f_{\rm cont}$, that reflects the probability that each SZE-optical pairing represents a real cluster rather than a random superposition of physically unassociated systems. The new MADPSZ cluster catalogue consists of 1092 MCMF confirmed clusters and has a purity of 85%. We present the properties of subsamples of the MADPSZ catalogue that have purities ranging from 90% to 97.5%, depending on the adopted $f_{\rm cont}$ threshold. $M_{500}$ halo mass estimates, redshifts, richnesses, and optical centers are presented for all MADPSZ clusters. The MADPSZ catalogue adds 828 previously unknown Planck identified clusters over the DES footprint and provides redshifts for an additional 50 previously published Planck selected clusters with S/N>4.5. Using the subsample with spectroscopic redshifts, we demonstrate excellent cluster photo-$z$ performance with an RMS scatter in $\Delta z/(1+z)$ of 0.47%. Our MCMF based analysis allows us to infer the contamination fraction of the initial S/N>3 Planck selected candidate list, which is 50%. We present a method of estimating the completeness of the MADPSZ cluster sample and $f_{\rm cont}$ selected subsamples. In comparison to the previously published Planck cluster catalogues. this new S/N $>$ 3 MCMF confirmed cluster catalogue populates the lower mass regime at all redshifts and includes clusters up to z$\sim$1.3.Comment: 20 pages, 5 Appendices, 17 figures, submitted to MNRA

The PSZ-MCMF catalogue of Planck clusters over the des region

We present the first systematic follow-up of Planck Sunyaev–Zeldovich effect (SZE) selected candidates down to signal-to-noise (S/N) of 3 over the 5000 deg2 covered by the Dark Energy Survey. Using the MCMF cluster confirmation algorithm, we identify optical counterparts, determine photometric redshifts, and richnesses and assign a parameter, fcont, that reflects the probability that each SZE-optical pairing represents a random superposition of physically unassociated systems rather than a real cluster. The new PSZ-MCMF cluster catalogue consists of 853 MCMF confirmed clusters and has a purity of 90 per cent. We present the properties of subsamples of the PSZ-MCMF catalogue that have purities ranging from 90 per cent to 97.5 per cent, depending on the adopted fcont threshold. Halo mass estimates M500, redshifts, richnesses, and optical centres are presented for all PSZ-MCMF clusters. The PSZ-MCMF catalogue adds 589 previously unknown Planck identified clusters over the DES footprint and provides redshifts for an additional 50 previously published Planck-selected clusters with S/N>4.5. Using the subsample with spectroscopic redshifts, we demonstrate excellent cluster photo-z performance with an RMS scatter in Δz/(1 + z) of 0.47 per cent. Our MCMF based analysis allows us to infer the contamination fraction of the initial S/N>3 Planck-selected candidate list, which is ∼50 per cent. We present a method of estimating the completeness of the PSZ-MCMF cluster sample. In comparison to the previously published Planck cluster catalogues, this new S/N>3 MCMF confirmed cluster catalogue populates the lower mass regime at all redshifts and includes clusters up to z∼1.3

Chemical Analysis of the Brightest Star of the Cetus II Ultra-Faint Dwarf Galaxy Candidate

We present a detailed chemical abundance analysis of the brightest star in the ultra-faint dwarf (UFD) galaxy candidate Cetus II from high-resolution Magellan/MIKE spectra. For this star, DES J011740.53-173053, abundances or upper limits of 18 elements from Carbon to Europium are derived. Its chemical abundances generally follow those of other UFD galaxy stars, with a slight enhancement of the alpha-elements (Mg, Si, and Ca) and low neutron-capture element (Sr, Ba, Eu) abundances supporting the classification of Cetus II as a likely UFD. The star exhibits lower Sc, Ti, and V abundances than Milky Way (MW) halo stars with similar metallicity. This signature is consistent with yields from a supernova (SN) originating from a star with a mass of ~11.2 solar masses. In addition, the star has a Potassium abundance of [K/Fe] = 0.81 which is somewhat higher than the K abundances of MW halo stars with similar metallicity, a signature which is also present in a number of UFD galaxies. A comparison including globular clusters (GC) and stellar stream stars suggests that high K is a specific characteristic for some UFD galaxy stars and can thus be used to help classify objects as UFD galaxies.Comment: 15 pages, 7 figures, 5 tables, accepted to Ap

Concerning Colour: The Effect of Environment on Type Ia Supernova Colour in the Dark Energy Survey

Recent analyses have found intriguing correlations between the colour ($c$) of type Ia supernovae (SNe Ia) and the size of their mass-step, the relationship between host galaxy stellar mass and Hubble residual. These analyses suggest that the underlying cause of this relationship is dust. Using a sample of 675 photometrically-classified SNe Ia from the Dark Energy Survey 5-year sample, we study the differences in Hubble residual for a variety of host and local properties for subsamples split by their colour ($c$). We find a $3\sigma$ difference for the size of the mass-step when comparing blue ($c < 0$) and red ($c > 0$) SNe. We observe the lowest r.m.s. scatter ($\sim 0.14$) in Hubble residual for blue SNe in low mass or blue environments, suggesting that these objects provide the most homogeneous sample for cosmological analyses. By fitting for $c$-dependent relationships between Hubble residuals and $M_\mathrm{stellar}$, approximating existing dust models, we remove the mass-step from the data but find significant remaining steps in rest-frame $U-R$, indicating that current dust modelling based on $M_\mathrm{stellar}$ may not fully explain the remaining dispersion in SN luminosity. The most dispersion is removed by instead accounting for a $c$-dependent relationship between Hubble residuals and global $U-R$, resulting in $\leq 1\sigma$ remaining steps in other environmental properties, suggesting that $U-R$ provides different information about the environment of SNe Ia to $M_\mathrm{stellar}$. This $c$-dependent $U-R$ relation implies that $U-R$ may be more closely linked to dust, motivating the future inclusion of galaxy $U-R$ colour in the correction for SN distance biases.Comment: 18 pages, 8 figures. Submitted to MNRA

A Search for Faint Resolved Galaxies Beyond the Milky Way in DES Year 6: A New Faint, Diffuse Dwarf Satellite of NGC 55

We report results from a systematic wide-area search for faint dwarf galaxies at heliocentric distances from 0.3 to 2 Mpc using the full 6 yr of data from the Dark Energy Survey (DES). Unlike previous searches over the DES data, this search specifically targeted a field population of faint galaxies located beyond the Milky Way virial radius. We derive our detection efficiency for faint, resolved dwarf galaxies in the Local Volume with a set of synthetic galaxies and expect our search to be complete to M V ∼ (−7, −10) mag for galaxies at D = (0.3, 2.0) Mpc. We find no new field dwarfs in the DES footprint, but we report the discovery of one high-significance candidate dwarf galaxy at a distance of 2.2−0.12+0.05Mpc , a potential satellite of the Local Volume galaxy NGC 55, separated by 47′ (physical separation as small as 30 kpc). We estimate this dwarf galaxy to have an absolute V-band magnitude of −8.0−0.3+0.5mag and an azimuthally averaged physical half-light radius of 2.2−0.4+0.5kpc , making this one of the lowest surface brightness galaxies ever found with μ=32.3magarcsec−2 . This is the largest, most diffuse galaxy known at this luminosity, suggesting possible tidal interactions with its host